The development of effective treatments for cardiac arrhythmia, including atrial fibrillation, is of great concern. Adipose pericardial tissue volume was recently found to be independently correlated with several heart ailments, including atrial fibrillation. Although the exact mechanism behind this is still being elucidated, there are several findings that point to the deleterious role of the pericardial fat.
It has been demonstrated that the fatty tissue in the pericardial space is actively releasing pro-inflammatory cytokines. The pericardial fat is directly in contact with the myocardium. As such, it represents a pro-inflammatory entity, causing chronic inflammation of the myocardium in contact with it. Several sources describe a positive correlation between the level of inflammation markers in biopsy samples of atrial tissue from surgery patients and the magnitude of their pericardial adipose deposits. Additionally, the amount of pericardial adipose tissue may be related to the occurrence of cardiac arrhythmia, such as atrial fibrillation. The fact that most of the triggers causing paroxysmal atrial fibrillation originate from the pulmonary veins or the area immediately surrounding them, and the fact that these areas also coincide with adipose deposits, further underscores the link between the presence of pericardial fat and atrial fibrillation.
Recently, moderately cold temperatures were proposed as a means to reduce subcutaneous fatty deposits. For example, it has been demonstrated that applying temperatures slightly below 0° C. to the skin for several minutes results in a significant reduction of the fat layer occurring over a few weeks. The mechanism that makes adipose tissue more susceptible to cold-induced injury likely is linked to the higher crystallization temperature of cytoplasmic lipids in adipocytes, compared with the freezing temperature of water in myocites and other collateral tissues. The initially cold-induced injury in adipose cells likely leads to apoptosis. The process continues with cell removal by phagocytosis, such as by activated macrophages.
Therefore, it is desired to provide a system, device, and method for treating cardiac arrhythmia by causing lipolysis within pericardial adipose tissue either alone or in conjunction with the ablation of myocardial tissue within the heart.